Since inflatable occupant restraint systems or airbag systems have come into widespread use in the automotive industry, it has been observed that there are certain instances in which it may be desirable to deactivate the airbag system, or a portion thereof, in a vehicle during the period in which the vehicle is in use. Exemplary of such instances is that present when a vehicle has airbags for both the driver and front passenger positions and a rear facing infant seat is placed in the front passenger position, not properly positioned for use with the airbag. Another example is that of a driver who is small in stature and must operate the vehicle from a seating position that is very close to the steering wheel of the vehicle.
Since practically all airbag systems presently in use are activated by transmitting an electrical signal powered by the vehicle electrical system, it has been suggested to provide switching to effect deactivation of the airbag system, or a portion thereof, on a selective basis. U.S. Pat. Nos. 5,324,074; 5,234,228; 5,161,820; and 5,544,914 are exemplary of such approaches.
Certain disadvantages, however, are noted in the prior art disabling systems. These disadvantages arise from the appropriate desire of the designer of the occupant restraint system to ensure that because of the inherent normal benefit of having the airbag system operating, the disabling takes place only when intended and only under control of the operator of the motor vehicle. It is also desired that the reliability and efficacy of this disabling device be monitored during a vehicle operating event which might normally give rise to operation of the airbag deactivated by the deactivation system. Further, it is desirable that one have the flexibility to selectively disable only the desired airbag(s) in a multi-airbag system.
Further, in order to minimize the cost to vehicle owners, preferably any airbag deactivation system will be easy and quick to install, generally using existing airbag system connections that are in place on a large variety of airbag equipped vehicles; and will be easily adaptable to various vehicles with common parts to further minimize the cost. Also, preferably, any changes to the existing airbag system will not detract from the current overall safety of the vehicle due to the new deactivation equipment.